Update:
I decided to throw caution to the wind and test the PSU's short protection by creating a short in the molex. The PSU and MB do the same thing as before when the short occurs. The PC shuts down but the power light stays on. I cannot reboot the PC until I flip the switch. Does this mean the PSU is shorting when I put the GPU under load and it's doing what it should, shutting down? If so does that means the PSU is not the problem and the board is shorting something when the GPU is under load? Is that even possible? OR does it mean the PSU is shorting when the power draw increases? That doesn't make much sense since I can stress the CPU, the memory, the FPU and the HDD in Aida64 all at once and have no problems. The only time the shut down occurs is when the GPU is stressed. Again though the GPU works just fine in another machine. Banging my head against a wall here.